Living organisms and individual cells continuously adapt to changes in their environment. Those changes are particularly sensitive to fluctuations in the availability of energy substrates. The cellular transcriptional machinery and its chromatin-associated proteins integrate environmental inputs to mediate homeostatic responses through gene regulation. Numerous connections between products of intermediary metabolism and chromatin proteins have recently been identified. Chromatin modifications that occur in response to metabolic signals are dynamic or stable and might even be inherited transgenerationally. These emerging concepts have biological relevance to tissue homeostasis, disease and ageing.

The authors argue that, among other things, methylation of histones is regulated by changes in the concentrations of some citric acid cycle metabolites. I find it difficult to imagine that the concentrations of the citric acid cycle intermediates could change significantly enough to act as allosteric effectors but that's not what grabbed my attention.

That's three NADH, one QH2, and one GTP (or ATP) for a total of ten ATP equivalents. The new version, published last week in the most prestigious science journal in the world, shows that there are six NADH produced per cycle for a total of 15 ATP equivalents. It must be correct because this is a paper about intermediary metabolism and it was reviewed by experts in the field. Unfortunately, the authors don't give a reference to this new information. I assume that it's common knowledge among the top metabolism researchers so they didn't bother citing the papers.

Can anyone out there direct me to the revolutionary papers that I missed?

P.S. I'm not even going to mention that FADH2 is NOT a product of enzyme-catalyzed β-oxidation.

I'm not a big fan of MOOCs but I just couldn't resist a course called "Evolution: A Course for Educators". The instructors are two Ph.D. employees from the American Museum of Natural History in New York (USA). As you probably know, the American Museum of Natural History is very proud of its tradition in education. Here's what they say on their website.

The American Museum of Natural History is one of the world’s preeminent scientific, educational and cultural institutions. Since its founding in 1869, the Museum has advanced its global mission to discover, interpret, and disseminate information about human cultures, the natural world, and the universe through a wide-ranging program of scientific research, education, and exhibition.

This is a course for educators and that's right up my alley. You may want to sign up as well. Here's the description and the video.

How are all of the species living on Earth today related? How does understanding evolutionary science contribute to our well-being? In this course, participants will learn about evolutionary relationships, population genetics, and natural and artificial selection. Participants will explore evolutionary science and learn how to integrate it into their classrooms.

....

The AMNH course Evolution: A Course for Educators provides an overview of biological evolution for educators. Informed by the recently released Next Generation Science Standards, the course explores the history of evolutionary theory and the evidence that supports it. We will learn about patterns of human evolution and societal implications of modern evolutionary biology, and how scientists determine relatedness among living and extinct organisms. Course participants will bring their understanding of course themes - along with content resources, discussion questions, and assignments - into their own teaching.

It's a bit disturbing that the Next Generation Science Standards don't mention random genetic drift, Neutral Theory, speciation, or population genetics [Natural Selection and Evolution] but the course promises to cover population genetics and I assume that it will also cover all mechanisms of evolution since it's being taught by an evolutionary biologist (Joel Cracraft).

The purpose of the course is to train the next generation of high school (and university) teachers. One of the instructors, David Randle, is an expect on education. We all know that teachers need to be updated on modern evolutionary theory.

It starts next Monday. I'll let you know how I'm doing when I write the first test.

Tuesday, October 29, 2013

Ross Firestone is a 2nd year MD/PhD student at the Albert Einstein College of Medicine. He is one of the winners of the MCAT Video Competition. Apparently the Khan Academy and the Association of American Medical Colleges were impressed with his presentations on evolution. You can see all six videos at Evolution and population dynamics.

I'm posting the first one on Evolution and Natural Selection. It's all about natural selection but it's a very strange kind of natural selection. The organisms are parthenogenic and each individual is genetically programed to have a certain probability of reproducing. One type has a 50% probability of reproducing and another type has only a 25% probability of reproducing. These probabilities seem to be independent of any competition between them. Each successful individual produces four offspring. After some time the number of one type remains constant (25% probability) but the number of the other type (50% probability) doubles with each generation. This is natural selection according to Ross Firestone.

"Naturally," I was disappointed that natural selection was the only mechanism mentioned. There's nothing about random genetic drift in this video and nothing about the stochastic nature of natural selection. But my face lit up when I saw that there was another video on "Alternative Selection: Learn about driving forces of evolution other than natural selection." This could almost make up for screwing up the description of natural selection.

Alas, the second video is even worse. The "alternatives" are group selection and artificial selection. It gets even more worse. The example of group selection is the grandmother hypothesis. According to Ross Firestone, the fact that grandmothers help their grandchildren survive is group selection.

The video on "Bottlenecks and the environment" is also quite interesting. I didn't know that that the peppered moth story is an example of a bottleneck. Did you?

I think these videos are horrible—so horrible, in fact, that the Khan Academy should take them down. What do you think?

Are you wondering why a 2nd year med student feels so confident that he knows enough about evolution to teach it to pre-med students? Me too.

Here's a presentation by Tracy Kovach, a 3rd year medical student at the University of Virginia School of Medicine. Sandwalk readers will be familiar with my view of Basic Concepts: The Central Dogma of Molecular Biology and the widespread misunderstanding of Crick's original idea. It won't be a surprise to learn that a 3rd year medical student is repeating the old DNA to RNA to protein mantra.

I suppose that's excusable, especially since that's what is likely to be tested on the MCAT. I wonder if students who take my course, or similar courses that correctly teach the Central Dogma, will be at a disadvantage on the MCAT?

The video is posted on the Khan Academy website at: Central dogma of molecular biology. What I found so astonishing about the video presentation is that Tracy Kovach spends so much time explaining how to remember "transcription" and "translation" and get them in the right order. Recall that this video is for students who are about to graduate from university and apply to medical school. I expect high school students to have mastered the terms "transcription" and "translation." I'm pretty sure that students in my undergraduate class would be insulted if I showed them this video. They would be able to describe the biochemistry of transcription and translation in considerable detail.

There are people who think that the Central Dogma is misunderstood to an even greater extent than I claim. They say that the Central Dogma is widely interpreted to mean that the only role of DNA information is to make RNA which makes protein. In other words, they fear that belief in that version of the Central Dogma rules out any other role for DNA. This is the view of John Mattick. He says that the Central Dogma has been overthrown by the discovery of genes that make functional RNA but not protein.

I wonder if students actually think that this is what the Central Dogma means? Watch the first few minutes of the video and give me your opinion. Is this what she is saying?

Better BiochemistryStudents have to write an exam called the MCAT in order to get into American Medical Schools (Canadians students also write the MCAT). The exam is created and marked by the Association of American Medical Colleges (AAMC). The format of the exam is changing in 2015 to include more biochemistry and molecular biology. This means that "pre-med" students will likely be taking more biochemistry and molecular biology courses.

The Khan Academy is taking advantage of the new MCAT in 2015 by posting a series of videos on basic biochemistry and evolution. The content is approved by the AAMC in order to make sure it is suitable for MCAT preparation. Here's what they say on their website [Khan Academy MCAT].

This collection is being developed for the revised MCAT® exam that will first be administered in spring 2015. Videos will be added to the collection through fall 2014. All content in this collection has been created under the direction of the Khan Academy and has been reviewed under the direction of the Association of American Medical Colleges (AAMC). All materials are categorized according to the pre-health competencies tested by the MCAT²⁰¹⁵ exam; however, the content in this collection is not intended to prescribe a program of study for the MCAT²⁰¹⁵ exam. The content is also included in the Pre-health Collection within MedEdPORTAL’s iCollaborative sponsored by the AAMC: www.mededportal.org/pre-health *MCAT® is a program of the AAMC and related trademarks owned by the Association include Medical College Admission Test, MCAT, and MCAT²⁰¹⁵. For more information about the MCAT exam visit : www.aamc.org/mcat2015.

So, how did the Khan Academy prepare the videos? They set up an MCAT Video Competition and picked the best ones. You can read about the winners at MCAT Video Competition Winners. It's an eclectic mix of people but 11 out of 15 winners are medical school students or graduate students. Keep in mind that teaching introductory subjects like evolution and biochemistry is hard and Teachers Have to Know Their Subject.

I'm going to look at the videos on evolution prepared by a second year MD/PhD student at Albert Einstein College of Medicine and videos on biochemistry prepared by a second year MD student at Harvard Medical School and a third year med student at the University of Virginia School of Medicine. Medical students are very bright and very confident of their abilities. We'll see if these students learned enough in their undergraduate courses to be able to create accurate videos that will help university graduates pass the MCAT.

Before looking at some specific examples, let me make a general comment on Khan Academy videos. I've looked at quite a few of them over the years and every single one I've seen is a "kindergarten-level" video. What I mean by that is that the level of the presentation is barely suitable for students beginning high school and in some cases they really are pitched at the level my three-year old granddaughter could understand in a year or two. They certainly aren't up to the level of any university course that I've ever taught.

These MCAT videos are no exception. But they are intended for students who are about to graduate from university. Most of these students will be getting a science degree. The mini courses are intended for students who are about to write the MCAT exam and this should represent the level of knowledge expected of medical students. As a general rule, the students who are preparing for the MCAT have achieved high grades in their biology and chemistry courses and in their biochemistry and molecular biology courses. They wouldn't be considering medical school if they weren't in the top 25% of their class.

Why are the videos pitched at such a low level of education? Is this truly representative of the quality of university education in American universities? Check them out for yourself at: Biomolecules.

I've said it before and I'll say it again. The top three criteria for good teaching are: (1) accuracy, (2) accuracy, and (3) accuracy. Everything else is in fourth place or lower and that includes style. If what you're teaching is not accurate then nothing else matters.

It is hard to teach an introductory science course. You have to go back to basics and make sure that what you cover all the fundamental principles and concepts and that ain't easy. That's why the best teachers in introductory courses are often senior professors and lecturers with plenty of experience behind them. They have learned what's important and what's not and they can tell the difference between wheat and chaff.

One of the first things you learn when you start teaching is that you have to know the content inside and out — it’s simply not enough to know the bare minimum that you expect the students to master, because as a teacher, you need to push just a bit farther to get them up there. You need to be able to lead them to knowledge, and you need to be able to point off in the distance to all the cool stuff they can learn if they continue. How can you inspire if you’re not drinking deeply from the Pierian Spring yourself?

Keep this in mind next time we discuss teaching evolution and biochemistry. Teachers have to be experts and it takes a lot of work to make sure you know your content. If what you're teaching is not correct then you are not a good teacher no matter what the student evaluations say. And it's not only a question of accuracy—as PZ points out, you need to be more than a few steps ahead of your students in order to inspire them to do better.

PZ Myers is hosting the next Carnival of Evolution [Guess who’s hosting the Carnival of Evolution?]. I tried submitting an article but I was unable to read the stupid fuzzy words that you need to type before submitting. Now I can't submit unless I log in. When I do that, my time seems to expire before I can enter the necessary information. Very frustrating.

So, I figured I would just add a comment on PZ's blog. Easier said than done. You have to log in to his blog and none of my usual names and passwords work. I'm beginning to understand why submissions to the Carnival of Evolution are way down.

Monday, October 28, 2013

When you find yourself in a hole, stop digging.
Will RogersI favor teaching biochemistry from an evolutionary perspective and I was pleased to see that ASBMB considers evolution to be one of the fundamental concepts in biochemistry and molecular biology [ASBMB Core Concepts in Biochemistry and Molecular Biology: Evolution]. (ASBMB screws up their description of evolution but at least their heart's in the right place.)

Unless they understand evolution, students can't really understand why some parts of a protein are the same in all species and other parts are quite variable. They certainly can't understand why you can construct a phylogenetic tree from sequences and why this tree closely resembles those trees made from comparing anatomy/embryology. They won't know why those molecular trees are consistent with a fossil record unless they understand evolution.

Last week's molecule was 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline (OHCU). It is an intermediate in the degradation pathway from uric acid (or urate) to carbon dioxide and ammonia. Uric acid is the main breakdown product in purine catabolism. Humans have lost activity of all of the enzymes of this pathway so they excrete urate. Most other species excrete ammonia, although in other animals some of the terminal enzymes have been lost.

Some textbooks do not show the uric acid degradation pathway since it doesn't occur in humans and those textbooks aren't interested in an evolutionary approach to biochemistry (e.g. Berg, Tymoczko, and Stryer). The other majors textbooks (Voet & Voet, Garrett & Grisham, Nelson & Cox [Lehinger]) all show uric acid converted directly to allantoin via urate oxidase. This reaction was shown to be incorrect about 15 years ago. The actual pathway from uric acid to allantoin involves two intermediates; 5-hydroxyisourate and OHCU.

The winner, for the second week in a row, is Jean-Marc Neuhaus. [Monday's Molecule #220]. Jean-Marc lives in Switzerland so I've made arrangements to fly over there to visit him and treat him to two fondues at the Pinte de Pierre-à-Bot in Neuchatel. Jean-Marc was kind enough to send me a menu [PDF]. There are about 30 different fondues to choose from. If you would like to join us you can leave a comment on last week's post.

Email your answer to me at: Monday's Molecule #221. I'll hold off posting your answers for at least 24 hours. The first one with the correct answer wins. I will only post the names of people with mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Sunday, October 27, 2013

Theme Genomes & Junk DNAI happened to stumble on this video where Trace Dominguez (@trace501) promotes the idea of junk DNA based on the C-value Paradox—a version of the Onion Test. It's good that he tells the general public about junk DNA but it's bad that he equates "noncoding DNA" with "junk DNA." It's really silly to tell people that the only important part of your genome is the 2% that codes for proteins.

Scientists believe that about 2% of our genome encodes proteins and about 8% has other functions. It is not true that all noncoding DNA is junk. No knowledgeable scientist ever said that.

I realize that the kind of presentation shown in this video doesn't lend itself to a detailed description of noncoding DNA functions but surely we can do better than this? Why not say that scientists have determined that genes make up about 2% of our genome and about 8% contains information necessary for the proper functioning of genes and chromosomes? The rest, about 90%, is thought to be junk?

Saturday, October 26, 2013

Attanasio et al. (2013) published a paper in Science where they identified several thousand possible enhancers that were active in the facial area of developing mouse embryos. About 200 of them appear to be controlling genes that determine the size and shape of the face. (Recall that there are about 20,000 protein-encoding genes in mammals.)

Lynn Yarris of Lawrence Berkeley National Laboratory in California (USA) wrote up the press release [What is it About Your Face?]. It's a really good press release that fairly represents the published work and explains some of the significance. There's no mention of junk DNA in the press release or the published paper.

This is what it looks like when science correspondent Alok Jha published it in The Guardian.

Though everybody's face is unique, the actual differences are relatively subtle. What distinguishes us is the exact size and position of things like the nose, forehead or lips. Scientists know that our DNA contains instructions on how to build our faces, but until now they have not known exactly how it accomplishes this.

Visel's team was particularly interested in the portion of the genome that does not encode for proteins – until recently nicknamed "junk" DNA – but which comprises around 98% of our genomes. In experiments using embryonic tissue from mice, where the structures that make up the face are in active development, Visel's team identified more than 4,300 regions of the genome that regulate the behaviour of the specific genes that code for facial features.

It's pretty clear that science correspondent Alok Jha doesn't understand what he's writing and it's about time we started publicizing the names of those science writers who mislead the public about science. The consensus among knowledgeable scientists is that at least 80-90% of our genome is junk. It's time for science writers to admit that the science favors junk.

Scientists have known for decades that a lot of noncoding DNA is functional. The idea that all noncoding DNA (98%) is junk is false. No knowledgeable scientist ever made such a claim. It is a myth perpetuated, in part, by ignorant science writers; albeit, aided and abetted by ignorant scientists. Scientists have known for fifty (50!!) years that gene expression is controlled by regulatory sequences in noncoding DNA. Scientists have known for at least that length of time that during embryogenesis different genes are turned on and off and that this is due, in part, to binding of transcription factors to those regulatory sequences (enhancers). Scientists have known for one hundred years that the morphological features of mammals, including humans, are controlled by genes.

Thursday, October 24, 2013

Better BiochemistryTansey et al. (2013) have described the five core concepts in biochemistry and molecular biology. These are the fundamental concepts that all biochemistry instructors must teach and all biochemistry students must understand.

I like the idea of teaching biochemistry from a concept-driven perspective and I like the five categories. However, I was not too pleased with the description of the core concept of evolution [ASBMB Core Concepts in Biochemistry and Molecular Biology: Evolution]. It's one thing to identify the main categories but you also have to get the concepts right if you are going to advocate teaching them!

Let's see how they do with the second core concept.

Matter and Energy Transformation

The Many Forms of Energy Involved in Biological Processes

The energetics of a biological system or process—be it an ecosystem, an organism, a cell, a biochemical reaction—conforms to and is understood in terms of the fundamental laws of thermodynamics. Biological systems capture and process energy from the environment in many forms including that emanating directly from the sun (photons through photosynthesis), heat from the environment (kinetic energy), and energy rich compounds produced by geothermal processes (e.g. sulfur compounds) or other organisms (e.g. carbohydrates). Energy from all sources is chemically converted into useful chemical and physical work in a controlled and regulated fashion. The potential
energy stored in chemical bonds can used to generate motion, light, heat, and electrochemical gradients; likewise, electrochemical gradients can be used to generate motion and new chemical bonds. The input of energy from the environment allows living systems to exist in a state of nonequilibrium with their environment. The discussion of energy and matter conversions in biological systems makes use of the physical concept of changes in Gibbs free energy, or ΔG.

I think we can all agree that a basic understanding of thermodynamics is an important core concept. However, I would have worded this paragraph somewhat differently.

First, I would have mentioned that organisms can capture energy from simple inorganic compounds such as H2 or those containing Fe2+. These are energy sources for many chemoautrophic bacteria. If you are teaching biochemistry from an evolutionary perspective, it's important that students understand how these organisms capture energy. That's the process that is most like the mechanism found in the earliest living cells.1

Second, I would have put more emphasis on using captured energy in biosynthesis pathways. The paragraph mentions that energy can be used to generate new chemical bonds but that doesn't convey the importance of the process. Think about bacterial cells growing and dividing in the ocean or plants growing from a single seed. Most of the energy goes into making proteins, nucleic acids, lipids, and carbohydrates.

Third, I would drop the reference to cells being in "a state of nonequilibrium with their environment." That conceptt is covered under "homeostasis."

Catalysis

Biologically relevant energy and matter interconversions do not occur rapidly enough (often by many orders of magnitude) to support life. In living systems, biological catalysts called enzymes facilitate these reactions. Enzymes are macromolecules, usually proteins or RNA molecules with a catalytic function. Enzymes do not alter reaction equilibria; instead, they lower the activation barrier of a particular reaction so that reactions proceed much more rapidly. The presence of powerful enzymatic catalysts is one of the key conditions for life itself.

Description of the rates of enzymatic reactions represents the subdiscipline enzyme kinetics. Key concepts of kinetics, including the definitions of the terms vo, Vmax, Km, and kcat, constitute a common language for biochemists and molecular biologists in discussing the properties of enzymes.

Students should be able to apply their knowledge of basic chemical thermodynamics to biologically catalyzed systems, quantitatively model how these reactions occur, and calculate kinetic parameters from experimental data.

This is pretty good. I would only add that there are some fundamental concepts of enzyme mechanisms that need to be covered. The idea of a transition state is important. I put a lot of emphasis on oxidation-reduction reactions as a core concept in biochemistry.

Coupling Exergonic and Endergonic Processes

Biochemical systems couple energetically unfavorable reactions with energetically favorable reactions to allow for a wider variety of reactions to proceed.

Students should be able to discuss the concept of Gibbs free energy, and how to apply it to chemical transformations, be able to identify which steps of metabolic pathways are exergonic and which are endergonic and relate the energetics of the reactions to each other.

I have a problem with this section. I don't think that the concepts of "exergonic" and "endergonic" processes are very important in biochemistry and I don't use them in my textbook. They're not found in many other textbooks, either. Also, the idea of "coupled" reactions is very poorly taught in biochemistry courses. It's almost never true that enzymes simply link up two independent reactions, one of which is "favorable" and the other "unfavorable." What usually happens is that a completely new reaction is catalyzed. For example, ATP is not hydrolyzed but, instead, a group transfer reaction is created. This important concept is covered in the next section but the authors do not appear to have grasped its significance.

Not only that, what does it mean to say that a reaction is "energetically unfavorable"? Usually this refers to the standard Gibbs free energy (ΔG°′) but one of the most important concepts in biochemistry is the difference between the standard Gibbs free energy change and the actual Gibbs free energy change (ΔG) inside the cell. In most cases ΔG = 0.

It's true that there are potential "endergonic" reactions occurring inside cells. Think about ATP hydrolysis, for example. The concentration of ATP is maintained at a high level relative to ADP and Pi so the Gibbs free energy change in the direction of hydrolysis is actually more negative that even the standard Gibbs free energy change. What this means is the the reverse reaction is extremely "endergonic."

However, it is simply not true that there are steps in metabolic pathways that are "endergonic" as the authors state. That statement reflects a profound misunderstanding of a fundamental concept in biochemistry. There will not be any flux in the "forward" direction of a metabolic pathway as long as even one reaction is "endergonic." All reactions have to be near-equilibrium reactions or reactions with a negative ΔG that's maintained because the enzyme activity is regulated to prevent the reaction from reaching equilibrium.

The important concept is "flux" or flow of metabolites in one direction along a metabolic pathway. There are many pathways where flux can occur in either direction as in the central part of the gluconeogenesis/glycolysis pathway or the citric acid cycle. Students need to understand what controls flux in one direction or another. They should know that, like water, metabolic flux cannot flow uphill.

The Nature of Biological Energy

In biological systems, chemical energy is stored in molecules with high group transfer potential or strongly negative free energy of hydrolysis or decomposition. These molecules, particularly ATP, provide the free energy to drive otherwise unfavorable biochemical reactions or processes in tightly coupled and highly controlled fashion. Most frequently, the free energy needed for a process or metabolic pathway is provided by group transfer rather than by hydrolysis. In this way, efficient energy transfer is optimized, while inefficient energy transfer to the environment (in the form of heat for example) is minimized.

Students should be able to show how reactions that proceed with large negative changes in free energy can be used to render other biochemical processes more favorable.

The essence of these statements is correct but it is not explained very well. The important concept is not that you "couple" a "favorable" reaction like ATP hydrolysis to an "unfavorable" reaction like synthesis of glutamine from glutamate and ammonia (ΔG°′ = +14 kJ mol-1).

The point is that the enzyme (glutamine synthetase) catalzyes a completely different reaction—a phosphoryl group transfer reaction—with a negative standard Gibbs free energy change of ΔG°′ = −18 kJ mol-1.

[see Moran et al. (2011): Introduction to Metabolism]
If there were an enzyme that catalyzed the first reaction involving only glutamate and ammonia then this reaction could easily occur inside the cell in spite of the positive ΔG°′. It would be a near-equilibrium reaction with steady-state equilibrium concentrations of glutamate that were very much higher than the concentration of glutamine.

It's likely that the concentration of glutamine would then be too low to support all the reactions that require it. That's why the reaction involving ATP is more useful. It means that the steady-state concentration of glutamine can be maintained a much higher concentration. This requires regulation of glutamine synthetase in order to prevent the reaction from reaching equilibrium.

It seems to me that the authors (Tansey et al.) have not thought about the fundamental core concepts. They are promoting widespread misconceptions about thermodynamics and metabolism and they are missing some important concepts. I've already mentioned flux. The other missing concept is oxidation-reduction reactions (electron transfer) and the importance of reduction potentials. NADH, NADPH, and QH2 are important energy currencies inside the cell—just as important as ATP.

Wednesday, October 23, 2013

We don't know how life on Earth originated. We're not completely ignorant because we have a good idea of basic biochemistry and we know which enzymes and pathways had to be present in the earliest cells. We're pretty sure that the first life forms captured energy by oxidizing inorganic molecules. We're pretty sure that the first cells formed in the ocean.

We also know from the fossil record that the first organisms were single-celled organisms that resemble modern bacteria in size and shape. We know that they appear more than 3 billion years ago and there were no complex organisms for another billion years. We know that the idea of a primordial soup is nonsense and that speculations about an RNA world are not helpful.

Other than that, all we have is informed speculation. The correct answer to the question of how did life begin is "I don't know."

Denyse O'Leary asks: Origin of life: How are we doing?. She is shocked to learn that scientists have not figured out all the details of how life began. She acts like she knows the answer. She acts like she has an explanation that accounts for all of the data and for the subsequent history of life.

Why isn't she sharing that information? How do the IDiots explain the origin of the first primitive cells more than 3 billion years ago?

Tuesday, October 22, 2013

Minda Berbeco once taught evolution and she was surprised that her students wanted to talk about religion. She decided to consult with Peter Hess, the director of religious community outreach at the National Center for Science Education (NCSE). Her blog post is on the NCSE website at: When Students Ask about Religion.

Peter Hess mentioned that many people see a conflict between science and religion so Minda asked him what she should say to such people. Hess replied ...

I would recommend citing examples from the numerous scientists who have integrated current science into their religious worldviews, scientists such as Kenneth Miller, Francis Collins, Robert Russell, and Father George Coyne.

Another tack would be to cite statements from theological figures, such as Pope Benedict’s statement in Communion and Stewardship (2002), when he was still Cardinal Ratzinger:

Converging evidence from many studies in the physical and biological sciences furnishes mounting support for some theory of evolution to account for the development and diversification of life on earth, while controversy continues over the pace and mechanisms of evolution. While the story of human origins is complex and subject to revision, physical anthropology and molecular biology combine to make a convincing case for the origin of the human species in Africa about 150,000 years ago in a humanoid population of common genetic lineage.

Let me be clear: I’m not suggesting that you cite the views of such scientists and theologians as authoritative. There’s a wide range of religious reactions to evolution, from rejection to embrace, and you may not feel comfortable in endorsing any of them. (Indeed, a teacher in the public schools is required not to endorse any of them in the classroom.) But many people who reject evolution for religious reasons are ignorant about, or have never been seriously exposed to, the range of religious reactions to evolution. It may come as a complete surprise to them that devout religious people—perhaps even people of the same faith—have no theological objection to evolution. And opening people’s horizons is part of what education is all about, isn’t it?

There's so much wrong with this advice that I hardly know where to begin.

First, Hess seems to assume that Minda Berbeco is a Christian because otherwise his advice makes no sense. Surely, he wouldn't expect an atheist like me to tell students that the Pope is an authority on evolution? What if the teacher is a Muslim, a Buddhist, or a Hindu? What should they say? (Peter Hess is Roman Catholic.)

Second, he says that the views of these scientists (and the Pope) should not be cited as authoritative but if he really believes that then why cite them at all? Why not cite those religious scientists who think there really is a conflict between evolution and their religious beliefs?

Third, just because some scientists have been able to rationalize their acceptance of evolution with their Christian beliefs does not mean that there's no conflict. That is not a very good way to teach students how to think critically. After all, there are scientists who believe in homeopathy and astrology but that doesn't mean there's no conflict between real science and those pseudosciences, does it?

Fourthly, I agree that opening people's horizons is an important part of education. That's why I would tell students that, yes, there is a very real conflict between science and religion. It's quite likely that your faith will be severely challenged if you learn about evolution and science. Many students have never been seriously exposed to the atheist position. Somehow I don't think that's what Peter Hess has in mind when he talks about "opening people’s horizons."

Peter Hess recommends that students visit the Christian accommodationist webpages on the NCSE website [Science and Religion]. So, fifthly, I recommend that NCSE offer a more balanced view of this issue where they point out that there are many scientists who believe the conflict is very real. (I would be happy to write something.) NCSE should also expand their discussion to include non-Christian views of evolution.

The purpose of a grant, after all, is to facilitate research. But the rationale has become curiously inverted: now the purpose of one’s research seems to be to get a grant ...
Jerry CoyneThis is a post for scientists and those who would be scientists.

These articles and commentaries focus on research but let's not forget teaching. There are far too many science teachers—expecially at the university level—who are doing a terrible job of teaching evolution and biochemistry. (And probably lots of other subjects but those are the ones I'm familiar with.)

Monday, October 21, 2013

Dan Graur discovered that the term "junk DNA" was commonly used in the 1960's—long before Susumu Ohno used "junk" in the title of his 1972 paper. This makes a lot of sense. Apparently the term was quite commonly used in Cambridge by people like Francis Crick and Sydney Brenner. (Perhaps you've heard of them?)

Meanwhile, a person named "ShadiZl" commented on one my posts and pointed me to a letter from Thomas Jukes to Francis Crick in 1979. Jukes, you might recall, was no Darwinian. He was a proponent of Neutral Theory and random genetic drift. The letter is archived on the National Library of Medicine (USE) site under a section devoted to The Francis Crick Papers: Letter from Thomas H. Jukes to Francis Crick.

The letter is interesting because it reveals how casually the "insiders" talked about junk DNA and about the adaptationist misconception even as far back as 1979. This was when Gould and Lewontin published the "spandrels" paper. It also reveals how misguided the creationists are when it comes to the history of junk DNA. They still think that it was "Darwinists" who "predicted" junk DNA based on their view of natural selection. (Do not read this letter if you are irony-deficient. It will only confuse you.)

December 20, 1979

Dear Francis:

I am sure that you realize how frightfully angry a lot of people will be if you say that much of the DNA is junk. The geneticists will be angry because they think that DNA is sacred. The Darwinian evolutionists will be outraged because they believe every change in DNA that is accepted in evolution is necessarily an adaptive change. To suggest anything else is an insult to the sacred memory of Darwin.

This additive is so pervasive that if no reason can be found for an evolutionary change, it is necessary to invent one. Kimura points out that one author attributed the pink color of flamingos to protective coloration against the setting sun. This type of thinking carries over into people who sequence mRNA. They claim that differences between rabbit and human globin mRNAs are because each species has its own requirements for secondary structure.

Various people have tried to think up possible functions for the regions of DNA that do not code for anything as far as is known. Roy Britten says that such DNA has a regulatory function.

Actually, the scheme proposed by Britten about ten years ago was that occasionally events of saltatory duplication, took place, so that a great many copies of a short piece of DNA were made. As time went by, the composition of a family of identical copies became changed by drift, until the copies no longer closely resemble each other. Figure 55 of the article by Britten shows a diagram of a sort of "junk DNA generating system". I note that he says on page 105 "the rate of increase in DNA content per cell resulting from saltatory replication alone may prove to be embarrassingly large and a mechanism for the loss of DNA may have to be invoked". I gather that you agree with this.

I quoted you on drift in DNA in a talk that I gave at the symposium for Emil Smith (see enclosure). Your concept of "junk DNA" presumably includes this idea. I shall look forward to hearing more about it, and I have been asked by Die Naturwissenschaften to write an article on silent changes, so I hope I can include mention of your new manuscript when I start to write mine.

The title of this post suggest a story that's about as interesting as the proverbial "Dog Bites Man" story [see Man Bites Dog]. Nevertheless, from time to time it is amusing to see how the creationist mind works.

Last week's molecule was citrate synthase, one of many enzymes that show considerable amounts of structural change during binding. It looks like the "induced fit" mechanism is a general feature of substrate binding and not something that is limited to just a few examples. That part of the question was easy but the second part was hard. Jean-Marc Neuhaus is this week's winner because he has a copy of my book and was able to look up the explanation. The important point to keep in mind when you are thinking about the thermodynamics of biochemical reactions is that most reactions are near-equilibrium reactions where ΔG = 0. In the case of the citrate synthase reaction, ΔG°′ = -31.5 kJ mol-1, in the direction of citrate formation. What this means is that the equilibrium concentrations of the products are very much higher than the concentrations of the substrates. These concentrations would be closer to being equal if the reaction was coupled to substrate level phosphorylation (e.g. ATP formation). This would be a problem since the concentration of oxaloacetate (substrate) inside the cell is very low. (Because the standard free energy change of the malate dehydrogenase reaction is ΔG°′ = +30 kJ mol-1) [Monday's Molecule #219]. Jean-Marc lives in Switzerland so I've made arrangements to fly over there to visit him and treat him to fondue at the Pinte de Pierre-à-Bot in Neuchatel.

Today's molecule is one of those molecules that students should never be asked to memorize. It's an intermediate in a very important pathway. Identify the molecule and the pathway. You have to give me the full name and the common abbreviation. Email your answer to me at: Monday's Molecule #220. I'll hold off posting your answers for at least 24 hours. The first one with the correct answer wins. I will only post the names of people with mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Tuesday, October 15, 2013

Better BiochemistryTansey et al. (2013) have described the five core concepts in biochemistry and molecular biology. These are the fundamental concepts that all biochemistry instructors must teach and all biochemistry students must understand.

Intelligent Design Creationists are upset when I call them IDiots. They don't realize that the easiest way to make me stop is for them to stop acting like ... well, idiots.

The IDiots are fond of pointing out that they are all good Christians who would never stoop so low. They are all kind and gentle people who treat their opponents with respect and dignity. That's why they get so upset when we insult them.

Denyse O'Leary and the people who comment on Uncommon Descent have made these points repeatedly. They are the good guys and we are the bad guys when it comes to describing your opponents.

She quotes a passage from Dawrin's The Descent of Man, and Selection in Relation to Sex.

The break between man and his nearest allies will then be wider, for it will intervene between man in a more civilised state, as we may hope, even than the Caucasian, and some ape as low as a baboon, instead of as now between the negro or Australian and the gorilla.

Darwin’s racism was not adopted out of bad will but simply as the logic of Darwinism. That is the point that every Darwinist wants to miss or downplay.

They have demanded that we all understand that the greatest man who ever lived wasn’t a racist and we are all misquoting or misunderstanding him or are bad, bad people or whatever for even bringing this stuff up.

Okay so we’re really awful here at Uncommon Descent. As our name implies, we don’t espouse any theory that says that humans are merely evolved animals or that we must inevitably form separate species as a result of isolation. Heck, we don’t even espouse a theory that says that separate species usually form that way. The evidence is mixed.

His believers are therefore stuck in the awkward position of having to pretend that what is obviously racist isn’t, and denouncing any of us who read the plain sense of it correctly.

Do you see the problem. Those poor IDiots are being criticized unjustly for seeing the obvious; namely, that all Darwinists are racists.

The second paper, by Tansey, et al., is the most important paper. It covers the results of a two-year study to define and describe the fundamental concepts that must be taught. The authors begin by explaining why it's important to agree on a core set of fundamental concepts.

Last week's molecule was cobalamin or vitamin B12. The structure was solved by Dorothy Crowfoot Hodgkin who won the Nobel Prize in Chemistry in 1964. There have been ten Nobel Prizes for work on vitamins and coenzymes. There were a lot of people who got this one right. The winner is Piotr Gasiorowski. The undergraduate winner is Jacob Toth [Monday's Molecule #218]. That makes four lunches that I owe Jacob. Right now, he's far away (British Columbia) but he may be coming to Toronto to collect. That may cut down on his chances of winning!

Today's molecule is a very common enzyme found in all species (I don't know of any exceptions). It's part of a pathway that's familiar to all biochemistry students. The figure illustrates a classic "induced fit" mechanism of substrate binding where the binding of one substrate creates the binding pocket for the second substrate. In this case, it's the homodimeric animal version of the enzyme showing rotation of the small domain of one of the subunits. Name the enzyme and the reaction it catalyzes.

There's more. In order to win a free lunch you have to explain something else. It's related to the fundamental concepts that all biochemistry students should know. The standard Gibbs free energy change for the reaction catalyzed by this enzyme is ΔG°′ = -31.5 kJ mol-1. What does that mean if you are trying to understand the reaction that takes place inside the cell? Is there a reason why this reaction isn't coupled to synthesis of ATP? I'm interested in seeing how most Sandwalk readers understand the fundamental concept of reaction thermodynamics.

Email your answers to me at: Monday's Molecule #219. I'll hold off posting your answers for at least 24 hours. The first one with the correct answer wins. I will only post the names of people with mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Keep in mind that Kevin is President of the National Center for Science Education. He isn't speaking for NCSE in this paper but it's fair to say that his view is quite compatible with those of other members of the NCSE leadership.

Here's what Kevin writes under the subtitle "Avoid pitting science against religion, even though sometimes there are real conflicts" ...

He wrote an article for Evolution: Education and Outreach in which he describes misrepresentations of evolution in textbooks (Padian, 2013). Since he is a prominent leader in the fight against creationism, we need to pay attention when he tells us how evolution should be taught in public schools.

Before examining some of those "misconceptions," let's review some earlier papers in Evolution: Education and Outreach. The very first issue contained an article by John N. Thompson where he defined evolution as ...

Evolution is quite simply heritable change in the genetic structure of a population. There is nothing in this or any similar standard definition of evolution that requires that genetic change in the average size, shape, or any other trait be maintained for a hundred, a thousand, or a million years before it can truly be called evolution. (Thompson, 2007)

Unfortunately, Thompson is under the mistaken impression that natural selection is the only significant mechanism of evolution but that's not the point. The point it that he, and many others, see evolution as a continuous and ongoing process that includes the minor fluctuations that Kevin Padian dismisses.

Friday, October 11, 2013

The latest issue of BAMBED (Biochemistry and Molecular Biology Education) contains a series of articles on "Foundational Concepts and Assessment Tools for Biochemistry and Molecular Biology Educators." The goal is to get teachers to change their way of teaching undergraduate courses in biochemistry and molecular biology.

The first paper is an introduction to "Promoting Concept Driven Teaching Strategies in Biochemistry and Molecular Biology" (Mattos et al, 2013). The authors point out that ASBMB (American Society for Biochemistry and Molecular Biology) has been advocating concept driven teaching strategies for over a decade. What they don't mention is that this advocacy has been remarkably unsuccessful The majority of biochemistry and molecular biology courses are still taught in a memorize-regurgitate format. Most American courses are taught to the MCAT. Understanding concepts won't get you a good grade on the MCAT.

The idea of teaching fundamental concepts is useful if biochemistry and molecular biology are foundational courses designed as prerequisites for more advanced study. That's not how biochemistry is seen in most America colleges. Students usually don't take the course until their junior year and many don't take it until they are seniors! These courses are not generally seen as prerequisites for other courses in the biological sciences.

That's not how it works in Canada where biochemistry is a second year course and it is a prerequisite for many third year and fourth year courses. The importance of concept driven teaching should be more obvious in Canada. It isn't, in my experience. That doesn't mean we don't talk about it—or course we do. We all think that teaching concepts is a great idea. Problem is, we don't do it in our introductory courses.

This is one of the reasons why MOOCs are seen as a viable alternative to in-class biochemistry courses. You can spew out facts for multiple choice exams just as easily on a video as you do in a classroom. If, instead, we were actually teaching a concept driven course using a student-centered approach, then MOOCs would seem ridiculous.

Mattos et al. (2013) report that ASBMB developed a three pronged approach ...

Building a network of scientists and educators focused on using and disseminating evidence-based teaching best practices.

Fostering both an understanding of the use of appropriate assessment, and the creation of a network of educators focused on defining the foundational concepts of the discipline, identifying key cross-disciplinary principles, and incorporating the appropriate skills necessary for students to succeed in the practice of science into the curriculum and assessment of student outcomes.

Promoting best practices in the education of our students by providing appropriate teaching and assessment resources for faculty.

They applied for, and received, a grant from the National Science Foundation (USA) to address these challenges. The results of those studies are ready to be published.

The next paper in this BAMBED issue describes the foundational concepts that all biochemistry & molecular biology instructors have to teach. Can you guess what they are before I post the answer? Put your best guesses in the comments.

Does science open minds, or close them? A "scientific view" is frequently taken as being basically synonymous with skepticism, questioning, and independent thinking. All good and wonderful things! Yet very often, self-proclaimed paladins of "science" are impatient with genuine skeptics, flee from debate, or find a variety of other creative ways to avoid having to confront challenges to their beliefs.

In the special October 23 edition of the Science & Culture Update on the Michael Medved Show, you'll have a chance to talk about science and skepticism, closed minds and open ones, live in the KTTH radio studio, with Mr. Medved, Darwin's Doubt author Dr. Stephen Meyer, and Evolution News & Views editor David Klinghoffer. All three are Discovery Institute senior fellows.

For the discussion, they'll take as a case in point the critical reception of Dr. Meyer's book, Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design, which has sparked furious debate -- and also a great deal of artful dodging of the relevant scientific issues by opponents of the theory of intelligent design. Why are critics of ID so determined to flee from a fair fight?

I think I'm going to try and listen in. I can't wait to hear how Medved, Meyer, and Klinghoffer respond to my scientific critique of Chapter 5: "The Genes Tell the Story?"

Thursday, October 10, 2013

John G. West is Vice President for Public Policy and Legal Affairs of the Center for Science and Culture (CSC)—the most important Intelligent Design Creationism propaganda organization. He is upset because some reporters describe Intelligent Design Creationism as a form of creationism. I've taken an excerpt from his post at Attempting to Win the Debate over Intelligent Design through Stereotyping and changed just a few words so you can get the gist of his argument.

The really discouraging thing here is not that some reporters are critical of evolution. It is that so many of them apparently see nothing wrong with preventing evolutionary biologists from defining their own position. This is a very strange way to do journalism, and if journalists started to apply their approach to evolution to other topics, I think it would become manifestly clear how unfair it is. Imagine, for example, a journalist deciding to use "Marxist" as a neutral label for President Obama based on the views of certain right-wing academics and political activists. Would that be regarded as fair or impartial by most journalists? Of course not. What if a reporter redefined Marxist to mean anyone who supports more active government? Would that make applying the term to Obama in a news story more defensible? Hardly. Yet when reporters label evolutionary biologists as "Darwinists," they are essentially doing the same thing.

What is really going on here is censorship. When reporters use as a "neutral" description of evolution a polemical smear invented by its critics, they are effectively silencing evolutionary biologists by not allowing them to speak for themselves. They are poisoning the well so no one will be willing to listen to the actual views expressed by evolutionary biologists. Journalists who write about evolution should re-read the Society of Professional Journalists' Code of Ethics, especially the provisions calling for them to "Support the open exchange of views, even views they find repugnant" and to "Give voice to the voiceless...."

Whatever a news reporter's views on evolution, he or she has a professional duty not to simply spread stereotypes and caricatures. That duty means nothing if it only applies to news coverage of groups and positions with which the reporter agrees. The real test of fairness for reporters is how they treat those with whom they disagree. When it comes to evolution, sadly, many reporters are failing the test.

Wednesday, October 09, 2013

The week is half over and nobody told me it's Quackery Week. Perhpas that's because it's only Quackery Week in the USA. The US Senate passed a resolution ...

A resolution designating the week of October 7 through October 13, 2013, as “Naturopathic Medicine Week” to recognize the value of naturopathic medicine in providing safe, effective, and affordable health care.

The petition is organized by Maya Fischer and Linda Cirella in Victoria, BC. Here's what they say ...

Our family tries to only buy food that is non-GMO or organic. The reason we're so concerned is because there have been no long-term studies showing that it is safe for people to eat or grow GMO foods. In fact, GMO studies on animals have shown infertility, immune system problems, accelerated aging, faulty insulin regulation, and changes in major organs and the gastrointestinal system. The American Academy of Environmental Medicine actually asks physicians to advise patients not to eat foods with GMO ingredients.

The really sad part is the message that those two women are sending to young girls across Canada. They're saying that science doesn't matter. You can just make up stuff to support your biases and prejudices.

A popular weapon used by those critical of agricultural biotechnology is to claim that there has been little to no evaluation of the safety of GM crops and there is no scientific consensus on this issue.

Those claims are simply not true. Every major international science body in the world has reviewed multiple independent studies—in some cases numbering in the hundreds—in coming to the consensus conclusion that GMO crops are as safe or safer than conventional or organic foods, but the magnitude of the research has never been catalogued.

Still the claim that GMOs are “understudied”—the meme represented in the quotes highlighted at the beginning of this article—have become a staple of anti-GMO critics, especially activist journalists. In response to what they believed was an information gap, a team of Italian scientists catalogued and summarized 1783 studies about the safety and environmental impacts of GMO foods—a staggering number.

The researchers couldn’t find a single credible example demonstrating that GM foods pose any harm to humans or animals. “The scientific research conducted so far has not detected any significant hazards directly connected with the use of genetically engineered crops,” the scientists concluded.

The research review, published in Critical Reviews in Biotechnology in September, spanned only the last decade—from 2002 to 2012—which represents only about a third of the lifetime of GM technology.

I snapped this picture on my way back from class. That's the science library on the left and the Medical Sciences Building on the far right. The tall buildings in the background are at the corner of College and Yonge in the heart of downtown Toronto.

It’s remarkably consistent how evolution and Genesis look at the process and tell the same stories using different words. Science can never prove or disprove God, but science can provide support for the existence of God and that is what the Big Bang and evolution can give us. There are, of course, holes in the theory of evolution that are big enough to drive a semi-truck through, but it is highly possible that evolution was the tool that God used to bring humans into being.

The Christians must be getting worried about all those atheist signs popping up on buses and billboards. Ken Ham and "Answers in Genesis" decided to strike back by hosting a 16 second video on an electronic billboard in Times Square, New York.

Watch the video if you dare.

I'm thinking that Young Earth Creationism and Christian fundamentalism aren't going to resonate too well with the average person in Times Square. This kind of publicity could really backfire by drawing attention to the large number of atheists in America.

Would this sort of thing ever have happened without Dawkins, Hitchens, Dennet, Harris and all those other obnoxious and disrespectful atheists who started making such a fuss just a few years ago? I think we're finally making progress and it's mostly due to them.

I've been having a discussion with Elizabeth Liddle in the comments to: Barry Arrington, Junk DNA, and Why We Call Them Idiots . I think it's important to understand why scientists first started thinking that most of our genome is junk. It's important to understand that these scientists were not Darwinists and their predictions were not based on an understanding of natural selection.

The subtitle of the paper is "Most evolutionary change in proteins may be due to neutral mutations and genetic drift" but that's not what I want to talk about. This paper is among the first to predict the presence of large amounts of junk DNA in our genome. King and Jukes didn't call it "junk"—that term was introduced by Susumu Ohno in 1972—but that doesn't matter. When King and Jukes talk about "superfluous DNA" they mean "junk."

Monday, October 07, 2013

Last week's molecule was α-tocopherol or vitamin E. You do not need vitamin E supplements and they may even be harmful. Lots of people got it right. The winner was Susan Heaphy [Monday's Molecule #217].

This is the week of Nobel Prize announcements so I've chosen an appropriate molecule. It is very complicated. So complicated, in fact, that there was a Nobel Prize for solving its structure. Name the molecule, the winner of the Nobel Prize, and the year it was awarded. You must get all three answers correct.

Email your answers to me at: Monday's Molecule #218. I'll hold off posting your answers for at least 24 hours. The first one with the correct answer wins. I will only post the names of people with mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Laurence A. Moran

Larry Moran is a Professor in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

Sandwalk

The Sandwalk is the path behind the home of Charles Darwin where he used to walk every day, thinking about science. You can see the path in the woods in the upper left-hand corner of this image.

Disclaimer

Some readers of this blog may be under the impression that my personal opinions represent the official position of Canada, the Province of Ontario, the City of Toronto, the University of Toronto, the Faculty of Medicine, or the Department of Biochemistry. All of these institutions, plus every single one of my colleagues, students, friends, and relatives, want you to know that I do not speak for them. You should also know that they don't speak for me.

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Quotations

The old argument of design in nature, as given by Paley, which formerly seemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

The world is not inhabited exclusively by fools, and when a subject arouses intense interest, as this one has, something other than semantics is usually at stake.
Stephen Jay Gould (1982)
I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.
Stephen Jay Gould (2002) p.1339
The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.
Stephen Jay Gould (1977)
Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.
Stephen Jay Gould (1980)
Since 'change of gene frequencies in populations' is the 'official' definition of evolution, randomness has transgressed Darwin's border and asserted itself as an agent of evolutionary change.
Stephen Jay Gould (1983) p.335
The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.
Stephen Jay Gould (1999) p.84

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.